How do I reduce feedback

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y2kindyz
Posts: 378
Joined: Mon Jan 05, 2009 10:54 am
Location: MISSION, TX

Re: How do I reduce feedback

#16 Post by y2kindyz »

Thanks Brent,

It has worked well for about 8 years of light home/party use. I guess being transported in and out of the truck on a cart shook something loose. I am going to try and open it up and see if I can see anything that is obviously wrong on the bad side. I hope it is maybe a loose connection.

Thanks again for all your input,

Oscar

y2kindyz
Posts: 378
Joined: Mon Jan 05, 2009 10:54 am
Location: MISSION, TX

Re: How do I reduce feedback

#17 Post by y2kindyz »

Ok I took the receiver home to do more testing. I opened up the unit and I powered it on. On the channel that is giving me problems the signal meter pegs when I tap on the circuit board. Other channel no movement. Does anyone know what I can look for that may be causing the issue? Or should I just give up?

Thanks,

Oscar

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Rune Bivrin
Posts: 521
Joined: Tue Aug 19, 2008 5:42 pm
Location: Stockholm, Sweden

Re: How do I reduce feedback

#18 Post by Rune Bivrin »

y2kindyz wrote:Ok I took the receiver home to do more testing. I opened up the unit and I powered it on. On the channel that is giving me problems the signal meter pegs when I tap on the circuit board. Other channel no movement. Does anyone know what I can look for that may be causing the issue? Or should I just give up?

Thanks,

Oscar
There's probably a bad solder joint somewhere. Not easy to locate, most of the time.

Quite often it's the larger components that this happens to, simply because they will vibrate more due to their size. In olden times it was surprisingly often the electrolytic capacitors that were the culprits. Or any component that warms up a lot, such as a power transistor or voltage regulator. There are three ways to locate these that I know of:
  • Looking long and hard with a magnifying glass
  • Gently tapping individual components with the handle of a small screwdriver
  • Using cooling spray on small areas to temporarily widen the crack in the solder
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